FES-PET/CT in Predicting Treatment Response in Patients with Endocrine Refractory, Recurrent or Metastatic Estrogen Receptor-Positive Breast Cancer

Inclusion Criteria

• Recurrent or metastatic cancer that is of known or suspected breast origin - may be biopsy proven or identified on standard imaging (e.g. CT, bone scan, magnetic resonance imaging [MRI], FDG PET/CT)
• History of ER+ pathology (ER+ may be confirmed from surgery or biopsy of primary breast cancer or lymph nodes, and/or surgery or biopsy of a metastatic site, metastatic biopsy is not required)
• At least one site of disease outside of the liver that is seen on standard imaging (e.g. CT, bone scan, MRI, FDG PET/CT); patients with measurable or nonmeasurable disease are allowed
• History of progression or recurrence of disease while on an endocrine targeted therapy containing regimen as assessed by medical record review of breast cancer history at screening
• Participants must be informed of the investigational nature of this study and provide written informed consent in accordance with institutional and federal guidelines prior to study-specific procedures

Exclusion Criteria

• Females who are pregnant at the time of screening will not be eligible for this study, urine pregnancy test will be performed at screening in women of child-bearing potential
• Inability to tolerate imaging procedures in the opinion of an investigator or treating physician
• Serious or unstable medical or psychological conditions that, in the opinion of the investigator, would compromise the subject’s safety or successful participation in the study
• History of HER2/neu positive cancer (IHC 3+ and/or fluorescence in situ hybridization [FISH] positive) as assessed by medical record review at screening